PHOS-CheK Australia

Phos-Chek Australia supplies one component of an intumescent coating to Formulators. These coatings are used to "passively" fight fire, by preserving the integrity of a structure for longer.

How Intumescent Coatings Work..

Intumescent coatins are normally applied by airless spray to provide a smooth decorative finish and in some cases can be an integral design feature. The coatings are designed to remain stable at ambient temperatures.

The composition of intumescent coatings is based on organic resin binders, which are typically acrylated rubber or epoxy. The resins are filled with active ingredients, which react in a fire at temperatures around 250°C to form a thermally insulating carbonaceous char or foam. The char can be expanded up to 50 times the original coating thickness. The char reduces the rate of heating of the steel and hence prolongs its load bearing capacity.

The basic formulation of an intumescent comprises a number of different elements: an organic binder; a carbonific; usually a penta or dipentaerythritol; a spumific or blowing agent which could be melamin or a formaldehyde derivative; a source of an acid catalyst such as ammonium polyphosphate or boric acid and finally a char reinforcement pigment such as glass flake or micro spheres.

As the temperature rises causing the binder to melt, the blowing agent liberates gases causing a controlled expansion. At the same time there is degradation of the carbon backbone and fusion of the inorganic reinforcing materials, resulting in char solidification.

Fact Sheet: 

Phos-Check P-30 Regular Fact Sheet.pdf

MSDS (Material Safety Data Sheet): 

P30.pdf